Vietnam ranks fifth in the world and first in Asia in the 2016 Happy Planet Index drawn up by the UK-based think tank New Economics Foundation. (Australia ranked 105 with a score of 20.5.)

The country scored 40.3 points in the index that measures sustainable well-being in 140 countries to show how efficiently residents of different countries are using environmental resources to lead long, happy lives.

The index, constructed for a fourth time since 2006, was based on four elements, including well-being, life expectancy, inequality of outcomes, and ecological footprint.

Vietnam had ranked second globally in 2012. It has a population of nearly 90 million, with a life expectancy of 75.5 years and per capita GDP of US$2,000.

According to NEF, Vietnam, characterized by its mountains and tropical forests, is one of just three countries in the top ten Happy Planet Index rankings with an ecological footprint small enough to be considered environmentally sustainable…

School enrolment is among the highest in the world at 98 percent in 2012, and the number of colleges and universities continues to grow rapidly…